How Bioluminescent Jellyfish Get Their Signature Glow

In the deep ocean where sunlight fades to black, a strange glow pulses through the water.

That glow comes from bioluminescent jellyfish , creatures that produce their own light using a chemical reaction. This glow is self-made, thanks to specialized cells and proteins in their bodies.

Bioluminescence is common among marine animals, from squid to sea cucumbers to single-celled organisms called dinoflagellates. But glowing jellyfish—especially comb jellies and deep-sea jellies—have perfected the art of underwater light.

How Jellyfish Produce Light

These jellyfish use a chemical called luciferin, which reacts with oxygen to produce light. The energy from that reaction releases photons, creating a visible glow.

Many species also rely on a protein called luciferase to control the reactio